Context

This document covers the steps to conduct a field survey of industrial “Functional Units” in Southwark. The focus is on collecting information about the physical characteristics of the “Building” and “Parcel” where industrial activities take place.

Key definitions

Building. Permanent roofed construction, usually with walls (OS Mastermap Topography Layer).

Parcel. Shapes that show the position and indicative extent of ownership for each registered property at ground level.

Functional Unit. The premises where a uniform industrial activity takes place, disregarding the type of tenure or physical structure of the space that accommodates the activity.

Exterior. A demarcated private land that contains one or more functional units.

Basemap

The basemap to conduct the survey is composed originally of two polygon layers: “Building” and “Parcel” which we conceptualize as “Functional Unit” and “Exterior” respectively. Polygons are closed shapes from which certain geometric properties can be derived (e.g. area, perimenter). There are more than 1000 “Functional Units” polygons on the basemap of the survey area each of which have a unique identifier, the Functional Unit Code(FUC). Similarly, “Exterior” units polygons have a unique identifier, however these are less polygons because they can have a one-to-many realtionship with the “Functional Units” (i.e. multi-units industrial estates).

Functional Unit Profile

To conduct the SIA survey we will use a Gographic Information System (GIS) database approach. Essentially, this means that the data we will collect is organised in such a way that each of the “Functional Units” polygons (spatial data) has a set of associated attributes (e.g. the answers to the survey’s questions) structured as a table. In the table each row corresponds to one polygon (with unique identifier) and each column corresponds to an attribute of the polygon.

The “Functional Unit” profile is the set of tabular information collected and the spatial data(polygons), which in some cases is updated or created by the surveyor. The “Exterior” units polygons data is also part of the “Funcional Unit” profile, although they have no associated set of questions. It is expected that the “Exterior” units spatial data is also verified or upadated during the survey to make it consistent with the corresponding “Functional Unit”.

Conducting the survey

The survey questions are classified according to the method used to obtain the answer in: Observed (from direct observation), Desktop (post field work) and Verified (surveyee answer). The collection of spatial data predominantly uses both methods: “Observed” (i.e. what you see on site) and “Desktop” (updating spatial data from your field notes). For the spatial data “Desktop” tasks you will be able to access the survey polygons in vector data digital format (“Functional Unit” and “Exterior”) and you are expected to edit them using a Geographic Informaton System(GIS) software package QGIS.

Hierarchical organisation of spatial units of study

The relations between the pre-existing and new spatial units of study follows a hierarchical structure. This logic is applied to the creation of unique identifiers of the units created or modified.

As a general rule no polygon should be deleted if it doesn’t have legacy.

3.1 Building marked as industrial but is vacant, derelict, etc.

In the case there is a Building polygon on the basemap sheet that you observe is no longer an industrial activity or it has ceased activities, the “Functional Unit’” should still be registered on EpiCollet according to the following:

Questions ‘Nickname’, ‘Map sheet number’, ‘FUC’, ‘1.1 Name of organisation’, ‘6.0 Additional notes…’, ‘7.2 Location’, ‘7.3 External photo’ should still be answered.

:information_source: In the cases described here, you shouldn’t be doing any modifications to the polyons on the digital file.

3.2 Building marked as industrial but is not industrial

In the case there is a Building polygon on the basemap sheet that you observe that has an activity with no relation at all to industrial uses (i.e. florist, child centre), the “Functional Unit’” should still be registered on EpiCollet according to the following:

Questions ‘Nickname’, ‘Map sheet number’, ‘FUC’, ‘1.1 Name of organisation’, ‘6.0 Additional notes…’, ‘7.2 Location’, ‘7.3 External photo’ should still be answered, and ‘SIC’ in cases that apply.

:information_source: In the cases described here, you shouldn’t be doing any modifications to the polyons on the digital file.

3.3 Small polygons with FUC adyacent to big polygons with FUC that are the same activity

In case there are polygons with unique FUC grouped together that appear to belong to the same FUC, is necessary to to do only one survey and annotate on the hard copy map which polygons share the same FUC. Then it is necessary to edit this by renaming the smaller polygons in QGIS according to the following process.

3.4 Parcel marked as industrial but is not industrial

Similar to case 3.2 but applied to the parcel. In this situation is necessary to edit the ‘PARCEL’ layer in QGIS following the same steps indicated in point 3.3 but changing the fields that apply according to the following:

5.1 Load web map base layer in QGIS

It is possible to load Google Maps (default and satellite maps, and other opendata sources) into QGIS as a basemap layer. Google Maps often has up-to-date information of commercial/retail activities that can be useful to contrast against what was observed and surveyed on the field. Also, the satelllite map offers a highly detailed description of the built environment allowing to identify buildings, fences, walls and other physical elements that can help improve the acurracy of the information registered.

There are two methods to load Google Maps (and other web map layers into QGIS)

5.2 Expert judgement data

The ‘Southwark Industrial Audit Atlas’ (all survey sheets) have been hand annotated highlighting places where there are industrial activities that have not been surveyed and other notes that can complement the field survey. The annotated altas sheets can be found here.

:warning: The areas identified as industrial in the annotated sheets that were observed as not industrial should be drawn and assigned a polygon ‘id’ with the following rule: 11111 + sheet number + correlative number (e.g. 11111 32 1 -without spaces). Although, these areas are spatial representations of a different nature than the FU they are still valuable for the purposes of the research. A survey form should be filled-in indicating the corresponding polygon ‘id’ (in the FUC field) and any observation in the section ‘6.0 Additional notes…’ when necessary. To draw a polygon follow the process detailed in point 8 of Part 2

5.3 Fire insurance maps and plans (Goad Maps) & planning applications

Particularly for the cases of railway arches additional detailed maps have been collected and organized for each sheet on this shared folder. These maps provide a higher-resolution description that can help outline a more precise shape of the units underneath the railway arches.

In the cases when polygons need small corrections follow the next steps. Select the layer to edit, turn the editing mode on and use the Vertex tool to edit the vertices of the polygons by clicking and moving. Add new polygons as required following the standard process.